Television



March 3, 1936. A. J. CAWLEY 2,032,526 I TELEVISION I Filed' Feb. 5, 1930 2 Sheets-Sheet 1 INVENTOR A @o' J I j March 3, 1936, 'A J, A E 2,032,526

TELEVI S ION Filed Feb. 3, 1933 2 SheetsSheet 2 INVENTOR Patented Mar. 3, 1936 UNITED STATES PATENT OFF-ICE TELEVISION Aloysius J. Cawley, Pittston, Pa. Application February 3, 1930, Serial No. 425,610

Claims.

The invention relates to improved methods of transmitting visual images of objects or pictures from one point to another by means of wireless or wire. Some of the objects of the invention 5 are as follows:

The provision of a plurality of concentric cylinders in contradistinction to disks for producing the image. One of those cylinders may be a mask to obscure the undesirable intersecting points of. the light permeable areas carried on the other two cylinders. Or the third cylinder may carry means for concentrating the light along the path of the intersections produced by the light permeable areas of the other two cylinders.

Improved means is provided for rotating two or more cylinders in opposite directions.

Improved means for framing the pictures are disclosed, particularly with the object in view of taking advantage of superposed projection of images. Also, a method of framing is provided wherein two intersecting points producing the scanning point traverse or scan the image field alternately. Also a method of scanning wherein stereoscopic pictures are produced which may also be colored, one modification using two wave sources, another using one wave train with a plurality of circuits containing the photoelectric elements. A method of framing is also disclosed which obscures the superfluous light dots and eliminates the rotating mask.

An improved method of scanning is disclosed that cuts the picture up into a series of dots rather than into a series of parallel dashes or lines as ordinarily used. This possesses the very desirable characteristic of chopping the carrier wave into a series of waves all of which are of the same number. That is, the picture is built up of a large number of trains of radio frequency, each train possessing exactly the same number of waves. The light and shade of the picture is produced by the variation of intensity of those wave trains, and this is their only point of difference, as their frequency is unaltered. This is 45 in sharp contrast to thevariations produced in the ordinary scanned line of a television picture.

Images are transmitted that may be of. a much greater width than height and thus more nearly approach the usual proportions of a theatrical stage. A method of rotating the cylinders horizontally is also disclosed, in which this broader than wide picture is obtained.

A projection process is disclosed which employs two or more projecting means placed at dif- 53 ferent angles to the screen, while the screen is provided with a series of ridges whereby the light from each projector is projected upon a certain series of surfaces of the ridges. That is, therig-ht hand projecting means projects the picture on the right handed surfaces, while the left hand -5 projector projects the light on the left hand surfaces. This gives three dimensional effects tothe screen.

A method of producing pictures by means of only two concentric cylinders is shown. -In- 1-0 stead of those cylinders having their light permeable areas in the form of openings made in opaque media, an arrangement is disclosed in which they consist of a number of cylindrical lenses, one series of lenses carried onone rotat- 1 5 ing medium concentrates the light into a line placedat a certain angle-while the other cylinder carries a series of cylindrical lenses that concentrates the light intoa line that is at an angle to the lines produced bythe other series 120 of lenses. The two series coact' to concentrate all of the available light into a bright spot, thus giving a very bright image.

A method is also shown whereby the scanning dot is produced by two concentric cylinders, while 25 a disk at an angle thereto carries either masking areas toobscure undesirable light intersecting points, or a series of cylindrical lenses to concentrate the light into a bright line along the path of the scanning dots ordashes.

A method of givinggreat strength and rigidity to the rotating cylinders which permits their light permeable surfaces to be in the closest possible contact. This causes the cylinders to. be held in their exact geometric position. Contact 3 wheels also act to hold the peripheral portions of the cylinders in apposition, thus avoiding. extinguishment of the intersecting scanning point.

A method of scanning in which oblong intersecting scanning bands are used, two of which 40 alternately scan a square field. Two dash scanning may be used instead of the oblong light point also with this system.

The production of rectilinear pictures in contradistinction to segmental pictures, such as those produced on a disk, etc.

To provide a system of dot or mosaic scanning, although the visual image is evenly illuminated, exposing only one dot or small area at a time.

Referring to the accompanying drawings forming part of-this specificationfln which like reference characters have similar meanings in all of the views,

Figure l is an elevational view of ascanning 55 apparatus which employs three concentric cylinders, two of which produce the intersecting light point which scans the picture, while the third acts either as a mask to hide the undesirable light points, or to concentrate the light away from the undesirable light point path and upon the desirable light point paths. Multiple aperture frames are shown with this apparatus.

Figure 1a shows a framing method which employs a frame which is literally a frame shown in Figure-1 cut into two halves, separate light sources and lenses being provided for either half. This produces two distinct pictures, which are scanned by two light points acting alternately. Those pictures may be superposedly projected both as regards right and left and from top to bottom.

Figure 1b shows the three rotating media used in one of the modifications of Figure 1. Two oppositely rotating cylinders produce the scanning point while the third rotating element cons ists of a series of cylindrical lenses which concentrate the light along the path of the scanning light dots.

Figure 1c shows the cylindrical lens of Figure 1b concentrating the light in a path of the scanning light dots produced by two oppositely moving media. The picture is here shown as being scanned in dots.

' Figure2 is a side view of the device shown in Figure l.

a Figure 2a is a sectional view of Figure 2, taken on a plane slightly to the left. of the vertical axis of Figure 2.

Figure 3 shows an elevational view of two concentric scanning cylinders and a very simple means for rotating them. There is no third element a stationary mask being provided which eliminates the undesired scanning points.

Figure 8a shows a modification of the two cylinders shown in Figure 3, which consists of a series of cylindrical lenses each carried on one of two concentric cylinders. These act to concentrate all of the light into a travelling light 45 dot.

Figure 3b shows that the rotating cylinders may have a blank portion thereon when used with such apparatuses that of Figure la. Or if but one series of images are to be produced 0 with the a paratus of Figure 1a then the lower portion of Figure 1b may be taken advantage of for a cylinder surface.

Figure 3c shows a plan viewof two concentric, oppositely rotating cylinders producing the travelling scanning point, while a disk rotating at right angles thereto provides either a mask or cylindrical lenses for concentrating the light along the path of the scanning points.

Fig. 3d is an elevation of a portion of the face of disc M1.

, Figure 4 is a side view in elevation of the mechanism for rotating thetwo concentric cylinders of Figure 3.

Figure 5 is an elevational view partly in cross section showing how the ends of the cylinders may be separated for the purpose of inserting reinforcing means, while the periphery of the cylinders which bear the light permeable areas are very close together.

Figure 6 illustrates a method of holding the two peripheral portions of the rotating cylinders ,Iin exact relation in order that the light passing through the scanning points may not be interrupted, due to lateral vibration of one or the other rotating cylinder. This figure as well as Figure 5 also discloses rims placed on the periphery of the cylinders in order to insure steady motion.

Figure 7 shows a method of scanning a square frame which utilizes two scanning points which alternately scan the picture area. The light permeable portions are shown in the form of two lines.

Figure 7a is a modification of Figure '7 in which dot scanning is used instead of the lines of Figure 7, each dot consists of a small rectangle which is twice as broad as high.

Figure 1 is a view of a television apparatus which may be used at the transmitting or receiving station, the only difference being that at the transmitting station a photoelectric cell is used,

while at the receiving station a neon lamp or other electro-optical element is used. As the function of the apparatus herein is principally that of scanning, it is deemed unnecessary to complicate the already too long specification by showing it in relation to the transmitting and receiving antennae and associated circuits. It'is well known that television may be produced by the alterations in brightness of a neon or other lamp which is in turn produced by the photoelectric alterations in a cell at the transmitting station in accordance with an image. The figure shows three concentrically mounted cylinders, two of which A and B rotate in opposite directions at nearly equal speed, while the third acts to eliminate the operation of undesirable light points produced by the intersecting light permeable areas of cylinders A and B, only the light points being permitted to function that are desired. The third cylinder M acts to either mask the undesired light points or to concentrate all of the light upon the path of desired light points. Shaft 2 is mounted upon suitable supports, such as those shown. Wheels I, 3 and 9, as is also cylinder A, are mounted rigidly upon shaft 2. Cylinders B and M are loosely mounted upon shaft 2. Wheel I is loosely mounted on shaft 2 also, and is attached to cylinder B, and rotates therewith. Wheel [3 is also loosely mounted on shaft 2 and is attached rigidly to the cylinder M. Stops l4 and I5 are rigidly attached to shaft 2 and act to hold wheels I and I3 in exact position as they are rotated. 'Power is applied to wheel I in any manner desired, such as by connecting a motor directly thereto, or by the use ofa friction wheel W, sliding along the radius 'of the wheel to produce varying'speeds. Shaft 2 turns wheel 3 which turns wheel 4. The wheel 4 is mounted upon the same shaft with wheel 6 'which it turns. Wheel 6 turns wheel 1 and conse- ,quently cylinder B. Thus it will be seen that cylinders A and B rotate in opposite directions, cylinder A rotating with shaft 2. Wheels 4 and S arenot of the same diameter, their difference in diameter being such that there is a difference in speeds between cylinders A and B that is in general equal to the number of pictures to be transmitted per second multiplied by the width of a picture. Different sized wheels 3 and 4 which are interchangeable may be used to produce any variation in the relative speeds of the two cylinders desired. Or 3 may be in the form of a sliding friction wheel (similar to W) which slides along 5 alongits radius to produce any variation in speed desired. The relative speeds of the two cylinders just described causes the light permeable series a to intersect with the light per- 'meable series b to produce an intersecting light dot, or scanning point in each of the image areas of the frame 1. Those dots are indicated by i. indicates the photoelectric element which is a photoelectric cell at the transmitting station and a neon or other lamp at the receiving station. The lens or optical elements for each of the image areas are indicated by Z. If the modification of the scanning method illustrated in Figure 1a is used, no third cylinder M is necessary. However, with the frame shown in Figure 1 a third element is used. Wheel 9 is rigidly attached to shaft 2, and meshes with and turns wheel 8 mounted on the same shaft with wheel In which is also turned thereby. Wheel l0 turns wheel ll mounted on the same shaft with wheel I2 which it turns. Wheel l2 meshes with and turns wheel I3. Wheel I3 turns freely on shaft 2 and is rigidly attached to cylinder M, also loosely mounted on shaft 2 and which is turned thereby. It Will be noted that cylinder M, due to the great reduction in the gearing used, travels at a rate of speed that is much slower than that of either cylinder A or B. This speed should be equal to the number of pictures to be transmitted per second multiplied by the width of a picture. In other words the masking areas m are turned at the same rate of speed as the rate of gain in speed of cylinder A over cylinder B. Thus, as a scanning dot traverses a picture, due to the excess of speed of A over B, the cylinder M moves at such a speed as to continually provide a clear space for the scanning dot 1 while obscuring the superfluous dots. The frame I is shown in this figure as having three image areas. The images from those areas may be superposed as desired by projection.

If the frame which cooperates with three vertically disposed single images shown in Figure 1 is divided into twice as many areas by a vertical partition, we have the frame shown in Figure 1a. A separate photoelectric element is provided for each area, whether three are used as in Figure 1, or 6 are used as in Figure 1a. In the latter figure a frame is shown which consists of three pairs of image apertures placed one above the other. It will be noted that the right vertical three image areas are in phase, while the left three image areas are in phase, but differ from the right. Either the right three or the left three image areas may be superposed as shown in Figure 2 upon screen Sc. As stated above, the right three produce an image that is different from the left three. Consequently, two carrier waves may be utilized, one of the right three and the other for the left three, suitable tuning means limiting the particular wave to its particular group of photoelectric elements. Each image space is provided for the right three and another for the left three areas. Any desirable shading means such as fl may be used on frame 1. The two image areas in two series a and b are shown and have the same significance as in Figure 1. Referring to the lower portion of Figure la it will be noted that intersecting point i has just scanned space S, while i is about to scan it. In space r light dot i has just scanned, and

the equivalent of light dot i is about to scan this picture entering from the right.

It is to be noted that the arrangement of the light permeable areas a and b in Figure la is equivalent to that obtained by eliminating the zig zag line of light permeable areas shown in Figure 1, say that commencing at the upper left hand corner and proceeding thence to the upper right hand corner of the second image'area in frame 1 and thence to the left and down, etc., and by further breaking the partition between two consecutive or adjacent image areas, making the image area oblong, being twice as high as it is broad. In Figure 1a, obviously the same scanning dot scans consecutively the right and then the left image area. It is to be noted in the scanning arrangement of Figure la that the number of scanning lines is not altered in any way, but their length is cut in half, and this is of much less importance than cutting down their number would be, as any particular scanning line varies its intensity with more or less continuity. Not much of the image producing property is lost. If any is lost, this may be compensated for by providing cylindrical lenses Zc which act tomake the picture either square or nearly so. However, their use may be rendered unnecessary by turning the scanning apparatus on its side and placing the cylinders in a horizontal position as shown in Figure 2, in this way the picture would be viewed as a rectangle that would be twice as wide as it is high, and thus more nearly approximate the proportions of the average theatre stage. The spherical lenses are shown at l for viewing or projecting the image upon a screeen, either as shown in Figure 2 as upon so with its ridges for producing stereoscopic effects indicated by 23. A color screen may be placed in front of each of the left vertical three image spaces, and may consist of red orange, while another screen such as blue violet may be placed in front of the right vertical three spaces. These may be superposed in the manner described or otherwise viewed directly to give color effects, as the left three and the right three produce different images.

Figure 1b shows an arrangement in which cylinder M is provided with a series of cylindrical lens 10 whose axes are placed in a horizontal position. As the cylinder rotates, the light is concentrated in a bright line or band along the course of the scanning points shown at to of Figure 10. A and B rotate in opposite directions as described, while the intersectiong portions of the light permeable areas cause a scanning of the image area by light points as shown by the dotted lines passing through the opening in the cylinders A and B and indicated by z. The light passes to the photoelectric element at the transmitter and from the electro-optical element (neon tube) at the receiver. Thus the undesirable light points will be eliminated, due to the fact that they are deprived of light, all of the light being concentrated in the path of the desirable light points 1.

Figure 1c shows a side view of Figure 1b, which is really a face view of the cylinder carrying the cylindrical lenses 10. Through this may be seen the desirable intersecting light point z, and its scanning path is indicated by ic. Point 1' is at the center of its scanning path. a and b are here shown as squares, and it is to be particularly noted that the scanning consists in opening successive squares along the light path ic. Only one square is opened at a time, the next square does not start to open until the one which has just beeen opened is fully closed. The picture is scanned by isolated squares, i. e., they are isolated in the point of time only (chronologically). They are however placed immediately in contact with each other, so that there is no space between adjacent squares. A chopper effect is produced, but the viewed scanned picture is perfectly homogeneous, as though made up of uninterrupted light.

, apparatus.

This method of scanning the picture in squares or other very small portions has the advantage over the usual method of scanning the picture in lines, and the line is interrupted with different frequencies, thus disturbing the radiated frequency of the waves. This acts to set up a series of broadcasted waves that differ greatly from one another from instant to instant and over almost all of the frequencies used in broadcasting, thus constituting the one great drawback in television. That is, many different frequencies of radio frequency are produced in the waves emanating from the transmitting station, making it almost impossible to confine the picture to its intended broadcast frequency. This difliculty does not exist in sound broadcasting, as the sound waves can only vary the carrier wave within the frequency limits of audio frequency. This difficulty in'transmitting television images is overcome by the method of scanning i. e. the type of scanning'media shown in Figure 1c and Figure 7a of this application. This method was also disclosed in my application Serial Number 391,541, filed September 10, 1929 for Scanning process, being disclosed in connection with Figure 8 of that application, and the present application is made a continuation in part of that application. By this methodof scanning, it will be noted that the picture is dissected virtually into fine squares, rectangles or circles, as the invention covers them all. Instead of the scanning path ie of Figure 10 being a long band, it is in reality a series of closely juxtaposed squares with no dark interval between them. Therefore, in the case of ordinary scanning the carrier wave is subjected to the uninterrupted influence of the band. However as this band traverses the image area and encounters the difsic is broken up into a number of minute squares,

circles, rectangles, etc. The carrier wave, in turn is chopped up intora large number of sections or trains, each train having exactly the same number of waves. Those trains differ from each other only in intensity. That is the wave trains differ from each other only in the amplitude of vibration of the waves which constitute those wave trains. There is no difference in the frequency or in the wave length of the waves constituting the various wave trains. Consequently there is no interference in broadcasting on other wave lengths than that of the broadcast carrier wave of the television transmitter.

This highly desirable feature of broadcasting television is also comprised in the method of scanning disclosed in my application Serial Number 380,202, filed July 22, 1929, entitled Television In that application, the picture was scanned also in virtual dots, instead of in dashes, as at present employed. This application is also a continuation in part of that application as regards themethod of breaking up the carrier wave into a number of units each of which are identical except for" the variation in intensity, or in other words, except for the variation in amplitude of the waves constituting the wave trains. Figure 1c shows an image area of a frame I. This process of breaking up the carrier wave into a number of identical frequency 'units is considered very important.

Figure 2 is a side view of the apparatus of Figmodification.

picture in horizontal lines.

.ure 1. It also discloses the fact that the cylin ders, whether two or three may be placed in a horizontal position. This is very desirous if the type of image aperture shown in Figure 1a, such as that at S, is used. If no cylindrical lens is used with S, the picture would then be twice as wide as high, thus more nearly approaching the proportions of stage theatres. Disks A, B and M have the same significance as in Figure 1. Disk M may be dispensed with in certain types of scanning, such as that of Figures 1a, 8b, etc. three apertures are shown in frame I attached to support and frame and housing 32, which also carries the photoelectric elements 5, one being provided for each image area or aperture. Support 32 is carried on movable arm 3|, which is in turn pivoted on shaft 2. 33 is merely a rest for the movable frame f and support 32. This aids in bringing the pictures into frame. The optical system for projecting the picture is shown at Z; there are three of them, one for each image. Those pictures are shown as being superposed upon the screeen Sc, which may or may not be provided with ridges 23. The figure shows a frame of three apertures as shown in Figure 1. However, the right or left three apertures of Figure 1a may be superposedly projected. Or, all six apertures of Figure la may be superposed into one image by projection. That is each three vertical areas may be superposed by vertical movement or focussing, and both of the resulting images may be superposed by lateral focussing. This is further illustrated in Figure 6.

Figure 2a shows a more detailed view of the framing, carrying and housing features of the apparatus. 3| is a movable arm which supports the frame 1 and housing 32 carrying photoelectric element (cell or lamp) 5. The cylinders A and B are shown, also cylinder M which may or may not be used.

Figure 3 is an elevational view of two concentric scanning cylinders, showing a very simple mechanism for moving them in opposite directions, also showing a means of shortening the bearings by supporting on a table like structure and permitting the cylinders to overhang the edge. There are only three gear wheels in this Surfaces A and B cause light permeable areas a and b to intersect, producing the light points i. A stationary frame I is shown which obscures the undesirable intersecting points i and permits points i to function. The image area is half as high as wide, approaching the dimensions of a theatre stage.

Figure 3a shows a modification of the moving media. Here the cylinders A and B are shown as carrying cylindrical lenses 0. and b. The lines indicate the axes of the cylindrical lenses.

A" and B move in opposite directions as by the mechanism shown in Figure 3. The lenses concentrate all of the light impinging upon the image area into a bright point which scans the This has the advantage of adding great brilliancy to the picture.

Figure 3b shows another modification of the,

scanning media. Here A is shown at the up per portion as having the left hand portion blank to obscure the left hand side of Figure 1a. The lower portion shows that it may be cut off at the center, leaving only a scanning medium over the right hand portion of Figure la. It is to be here noted that the arrangement of scanning shown in Figure 1 may be altered by cutting out the partition between adjacent scanning areas of frame ,1, thus making the image area oblong 2| are in the closest possible apposition, as they.

instead of square. By omitting the chain of light permeable areas a and 1) commencing at the upper left hand portion and passing thence to the lower right hand portion of the upper square and thence to the left, thence to the right, and so on, a scanning arrangement is obtained that is similar to the right hand portion of Fig ure 1a or of that shown in Figure 3b.

Figure 3c is a plan view of an apparatus using two scanning cylinders A and B that rotate in opposite directions. The mechanism is the same as that of Figure 3, with the addition of a few elements. In both Figure 3 and 30 wheels I and 3 and disk B are firmly attached to the shaft, while wheel I and disk A move freely on the shaft and are attached to each other. Power moves wheel I, shaft 2, wheel 3 and cylinder A in one direction. Wheel 3 moves wheel 4 and the latter moves wheel I together with cylinder B. The gear surface of wheel 4 is made broad so that wheel '5 meshes with it at the periphery, while wheel 3 meshes with it nearer the center. This causes A to have a faster speed than B and produces the scanning progression, or the shifting of the scanned line. In addition to Figure 3, the apparatus shown in Figure 30 comprises a wheel 34 placed on the same shaft with and moved by wheel 4. Wheel 34 meshes with wheel 35 mounted on the same shaft as disk Ml. Thus disk M2 is turned at a much slower rate than either A or B. 5 indicates the photoelectric element. Cylinders A and B produce the scanning light dot 2', as described in connection with Figures 1 and 3, while the disk Ml may carry either a mask m, as shown in Figure 3d to cover undesirable light intersecting points, or a series of cylindrical lenses as shown in Figure 1b at Ic.

Figure 3d is a sectional elevation view of the face of the disk Ml. It shows a three image area frame I with their three pairs of intersecting light permeable areas a and b, with areas m masking the undesirable intersecting light points.

Figure 4 is a side view of Figure 3, showing the simplicity of the mechanism. Shaft 2 carries wheel 3, which meshes with wheel 4, carried on shaft 2a. This is merely to augment Figure 3 as far as illustration is concerned.

Figure 5 is intended to illustrate the fact that great rigidity may be given to the concentric cylinders, while permitting their surfaces to come into close apposition without touching. This is due to the fact that there may be great separation of the ends of the cylinders A and B, thus permitting the use of elaborate reinforcing disks, etc., While their surfaces carrying the light permeable areas may be in close apposition. This insures accuracy of scanning. Means for reducing the friction are also illustrated. Rims 22 are shown as attached to the cylinders in order to assist in giving symmetrical motion thereto, i. e., to insure steadiness and eliminate vibration. Cylinder A is shown rigidly attached to the shaft 2, on either side of it are placed the large reinforcing disks IE to give rigidity to the cylinder. Cylinder B is shown mounted on ball bearings, the central portion being shown at I1 and as being rigidly attached to the shaft. The balls are shown at 200.. The cylinder B is fixed between the moving elements in the ball bearing structure. Those moving elements are shown at l9. Gear wheel I is rigidly attached through a spacing element to the movable portion l9, and thus moves rigidly with cylinder B. A ball bearing is shown between movable element l9 and H5 at 20. It will be seen that the cylindrical surfaces are independent of the distances between cylinder ends.

Figure 6 shows a means intended to prevent lateral vibration of the moving cylinders A and B. 26 are two wheels, one of which bears against the end of. cylinder A, while the other bears against the rim 22 attached to cylinder B. Wheels 26 are of large diameter and of little friction. 21 is the casing of the apparatus, showing the viewing aperture.

Figure '7 illustrates another method of scanning a picture which employs two alternately scanning light points i and Media A and B carry light permeable bands or and b. The image area in the frame 1 is here square. The dotted lines show the relation of the scanning lines. to the visual area; A diagonal line runs from the upper right hand corner to the left middle portion of the side of the square, while another runs from here to the lower right hand corner. a and b should have this length and inclination, a and b are shown displaced from this dotted line in order to illustrate the fact that i has just scanned asindicated by the dotted tail of an arrow, while i is just entering the visual field, and is about to scan the line indicated by the dotted arrow head. Obviously a visual image area may be scanned that is wider than it is high by drawing lines similar to the instructions given in connection with the description of the broken lines, and arranging the light permeable areas accordingly.

Figure '7 shows a modification of the scanning arrangement illustrated in Figure 8. Here instead of the uninterrupted bands, we have a made up of a series of steps of rectangular openings, while b is also made up of a similar series of openings. This will produce the same type of scanning as described in connection with Figure 1c, the difference being that here the dots consist of rectangles rather than squares. Only one point is illuminated at a time. The next rectangle starts to admit light just as soon as the previously illuminated rectangle is completely closed. Thus, we have a series of wave trains sent out by the transmitting station and received by the receiving station, each train being identical with its fellows as regards frequency and wave length of the waves constituting the wave train, the only difference being in amplitude of .vibration of the waves. And it is this variation in amplitude that produces the picture, furnishing the lights and shade.

It is to be understood that the apparatus is very flexible. For instance, the journal caps in Figures 1 and 3 may be lifted off after loosening the necessary bolts and disk M together with any of its gear wheels removed. The caps are replaced and this leaves the apparatus consisting of only two cylinders.

Having described my invention, I claim as new and desire to secure by Letters Patent:

1. A television apparatus consisting of three concentrically mounted cylinders, the cylindrical surfaces of said cylinders overlapping and their bases adjacent, light permeable areas carried on two of the cylindrical surfaces of said cylinders which intersect to form transversely moving light points, a frame associated with said cylindrical surfaces in which said light points move, light masking areas carried on the third of said cylindrical surfaces which act to obscure all but one of said light points in said image area at any instant.

2. A television apparatus consisting of three 152 differentially moving,

concentrically mounted cylinders, a motor connected through suitable gearing to differentially move said cylinders, the bases of said cylinders being adjacent and their cylindrical surfaces 53 overlapping, an image frame in cooperative relation with said cylindrical surfaces, light permeable areas on'two of said oppositely moving cylindrical surfaces which intersect to form transversely moving light points in said frame,

10,. the third of said cylindrical surfaces carrying a 20?: form moving light points to control the passage of light through the plane of said surfaces, a frame in relation to said surfaces in which said light points move, light masking areas carried on the cylindrical surface of the third of said cylin- 25 ders surfaces which act to limit the number of said light points to one in said image frame, suitable gearing for difierentially moving said cylinders and a photoelectric element in relation with said. v

frame.

4. A television apparatus consisting of two p;

and a photoelectric element cooperating with each of said apertures. a.

5. A television receiver consisting of a plurality of image varied light sources, a frame adjacent said light sources, two distinct apertures formed in said frame each of which cooperate with one of said light sources to form a single image in said frame, two oppositely moving, overlapping media located between said light sources and said frame, light permeable areas carried on said moving media which intersect to form scanning light points, but one of said points moving in each of said apertures at a time to form a single image.

ALOYSIUS J. CAWLEY. 

